70 Low

Worcester Bosch 70 Fault Code

The Worcester Bosch 70 fault code means: this code indicates your boiler is displaying its programmed technical heat output rating rather than a fault, meaning the system is currently operating normally.. It appears on 1 Worcester Bosch model in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Heat output 21.1 kW / Heat input 21.4 kW (RD532i L.P.G) or Heat output 26.0 kW / Heat input 26.3 kW (RD537i L.P.G)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Worcester Bosch models that show the 70 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch 70 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026